In a conventional infant incubator as shown in FIG. 1, an access port 11 is used to nurse a premature baby 12 so that a nurse's hand (not shown) is accessed in the space partitioned by a transparent plate or hood 13. This access port 11 comprises a tubular flexible sheet 14 folded at about half portion in length, an inner frame 15 mounted to the hood 13 and receiving at its inner rim of the flexible sheet 14, and a rotatable outer frame 16 concentrically movably disposed on the inner frame 15 and receiving at its outer rim of the flexible sheet 14 to adjust the opening degree of the access port 11 by squeezing the flexible sheet 14 by the rotation of the outer frame 16.
In the access port 11, the closed sheet 14 can support a medical tube 17 to be inserted. For example, after an artificial respiration tube 17 or cables (not shown) of an electrocardiogram are attached to a mouth or other body portions of the premature baby 12 in the infant incubator 10 through the access port 11 and the access port 11 is then closed, the inner space of the infant incubator 10 is substantially isolated from the outer space or atmosphere. Then, the desirable medical treatment is performed without disturbing the inner space of the infant incubator.
This access port 11 is so assembled that the outer frame 16 is easily rotated on the inner frame 15 to easily and rapidly access the premature baby 12 mentioned the above.
However, the easy and rapid access through the access port 11 causes the temperature or humidity control in the inner space to be more difficult since it is difficult to retain the outer frame 16 at an arbitrary position against the inner frame 15. Therefore, the access port 11 is apt to be opened by the self-weight or movement of the respiration tube 17 or cable even if the flexible sheet 14 is squeezed to be completely closed when the respiration tube 17 is inserted into the infant incubator 10 through the access port 11.
For example, when the medical treatment or monitoring of the premature baby 12 in the infant incubator is performed, the respiration tube 17 or cables are attached to the premature baby 12 through the access port 11. The access port 11 is closed to isolate the inner space from the ambience after the respiration tube 17 or cables are attached. However, the flexible sheet 14 of the access port 11 must be able to support the weight of mainly the respiration tube 17 and outer force due to the movement or offset of the respiration tube 17 or cables which is generated by the movement of the premature baby 12, or uncarefullnesss of the nurse or doctor walked around the infant incubator. When the outer force is applied to the flexible sheet 14 of the access port 11, the outer frame 16 is rotated to open the flexible sheet 14 of the access port 11. Then, it is necessary to frequently confirm or monitor the condition of the access port 11 and then adjust the access port 11 to be closed as necessary. If this adjustment to the access port 11 is not frequently performed, the access port 11 is apt to be gradually opened to leak the controlled air in the infant incubator to an unpermitable level.